CONSTITUTION AND DEVELOPMENT OP TKRMTTES, 17 



So considerable a delay in maturation appears only natural 

 if it is recollected that examples are selected for the throne 

 at a time when their generative organs are very backward in 

 development. 



Forms destined to become substitutes may be said generally 

 to become re-infected with Protozoa at the end of a week or 

 ten days ; they lose them in about a month at the succeeding 

 moult, but may subsequently re-acquire them. Too much 

 importance should not be attached to these facts, because 

 they are exhibited when the nests are mostly in bad con- 

 dition. 



From the foregoing observations I infer that the transfor- 

 mation of ordinary into substitute forms must be dependent 

 on a change, either quantitative or qualitative, in the cha- 

 racter of the ordinary diet. This is a necessary sequence from 

 what can be made out in the tube-nests, in which, in fact, we 

 have seen that a small quantity of decayed wood suffices not 

 merely to keep the Calotermites alive, but to enable them to 

 rear up substitute forms. 



I shall therefore record a series of observations on the 

 aliment of Calotermes, which have been carried out by 

 means of tube-nests. 



Their food and drink consist of — 



1. Wood. 



2. The matter excreted or disgorged by other Caloter- 

 mites. 



3. The exuviae of each other. 



4. The corpses of other Calotermites. 



5. Their own saliva or that of others. 



6. Water. 



*Calotermites triturate dead or dry wood (and cork) with 

 their mandibles, and devour the fine meal which is thus 

 obtained. This meal is not wholly used for food, but, as we 

 have mentioned more than once, is employed partly for build- 

 ing, and is also partly regurgitated (vide infra). Wood is 

 therefore the basis of the alimentation of Calotermes. 



The insects are consequently nourished on a material very 



VOL. 40, PART 1. — NEW SEK. B 



